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Evaluation of the toxicity of onyx compared with n-butyl 2-cyanoacrylate in the subarachnoid space of a rabbit model: an experimental research
No full textATILLA, PERGIN/0000-0001-5132-0002The toxic effects of onyx, its solvent dimethyl sulphoxide (DMSO), and n-butyl 2-cyanoacrylate (NBCA) were evaluated after infusion into the subaracnoid space of a rabbit model. Each of the two various concentrations of onyx, pure DMSO, NBCA, and normal saline solution were percutaneously infused into the pontocerebellar cisternae of 39 domestic male albino rabbits, after which, the brain stems and medial cerebellar tissues were harvested for biochemical and histopathological studies. The specimens infused in various concentration of onyx, DMSO, and NBCA showed neural tissue necrosis and edema with inflammatory cell infitration in the acute stage. Although the mean values of the lipid peroxidase in the control, saline, and NBCA groups were found to be almost similar, they were found to be low in the onyx and DMSO groups. This experimental study suggests that NBCA, and various concentrations of onyx and DMSO have toxic effects on the neural tissues of rabbits when infused into the subarachnoid space
Parkinson Hastalığı Hücresel Modelinde İnflamasyonun ve İnflamasyon Sonrası Uygulanan N-Asetilsisteinin H4 Hücrelerindeki Lag3 ve Tlr2 Reseptörleri Üzerine Etkisi
No full textKaya, Z.B., The Effect of Inflammation and Post-Inflammatory Administration of N-Acetylcysteine on LAG3 and TLR2 Receptors on H4 Cells in the Cellular (In Vitro) Model of Parkinson's Disease, Hacettepe University Graduate School of Health Sciences, Histology and Embryology Program Doctor of Philosophy Thesis, Ankara, 2021. Parkinson's disease is a complex, multifactorial neurodegenerative disease that has prevalence of 1% over the age of 55. Pathological hallmarks of Parkinson's disease include the loss of dopaminergic neurons in the substantia nigra pars compacta and the accumulation of inclusion bodies that contain predominantly alpha-synuclein (α-syn) and ubiquitinated proteins, called Lewy bodies. Although the formation of α-syn occurs intracellular, it can also be translocalized to extracellular space and then taken into the other cells via receptor mediated endocytosis. TLR2 is a well known receptor which detects extracellular α-syn and modulates the uptake of the protein by other cells. Uptaken α-syn is known to trigger expression and secretion of inflammatory cytokines such as TNF-α, IL-1β, IL-2 and IL-6 and induce neuroinflammation, apoptosis and mitophagy that results in cellular death. N-Acetylcysteine (NAC), an anti-inflammatory and anti-carcinogenic drug, has gained some focus to circumvent the detrimental effects of neuroinflammatory response. In this thesis, we hypothesized that, NAC treatment will result in anti-inflammatory response that restrict in vitro apoptotic and neuroinflammatory response by modulating transcription and expression of TLR2 and LAG3 receptors. In order to test this hypothesis, WT α-syn overexpressing human neuroglioma (H4) cell line was treated with TNF-α to induce inflammation and NAC, as anti-inflammatory drug to recover from deleterious effects of TNF-α induced inflammation and apoptosis. α-syn protein transcription and expression were validated by q-PCR and Western Blot, respectively. Cell viability was measured by Toxilight assay, and apoptosis was evaluated by Western Blot and TUNEL methods. We observed that NAC treatment diminishes inflammation mediated toxicity and cell death by altering transcription and expression of TLR2 and LAG3 receptors. Thereby, this study demonstrates NAC to be a promising candidate to recover from neuroinflammation that occurs in Parkinson’s Disease.Kaya, Z.B., Parkinson Hastalığı Hücresel Modelinde İnflamasyonun ve İnflamasyon Sonrası Uygulanan N-Asetilsisteinin H4 Hücrelerindeki LAG3 ve TLR2 Reseptörleri Üzerine Etkisi, Hacettepe Üniversitesi Sağlık Bilimleri Enstitüsü, Histoloji ve Embriyoloji Programı Doktora Tezi, Ankara, 2021. Parkinson hastalığı, bir çok sistemin etkilendiği nörodejeneratif bir hastalıktır. Hastalığın prevalansı genel popülasyonda binde 2-3, 55 yaş üzerinde ise %1 oranındadır. Parkinson hastalığındaki patolojik değişiklikler substantia nigra pars compacta'daki dopaminerjik nöronların kaybı ve hücrelerin içinde Lewy cisimciği olarak adlandırılan, ağırlıklı olarak alfa-sinüklein (α-syn) ve ubikutinlenmiş proteinler içeren küresel inklüzyon cisimciklerinin saptanması şeklindedir. α-syn proteinin nöronlarda hatalı katlanmalar sonucu hücre içinde çeşitli yerlerde birikebildiği gibi hücre dışı alana da geçebildiği bilinmektedir. Hücre dışı alana geçen α-syn proteini özellikle nöronlar ve glia hücreleri tarafından hücre içine endositoz yolu ile alınır. Endositozda TLR2 ve LAG3 reseptörlerinin rolünün açıklanabilmesi için çeşitli çalışmalar yapılmaktadır. α-syn proteininin endositozu, TNF-α, IL-1β, IL-2 ve IL-6 başta olmak üzere çeşitli inflamatuar sitokinlerin üretimine ve salınmasına sebep olmanın yanı sıra; hücre içinde mitokondriyal yolak üzerinden apoptoz ve mitofajiyi tetikleyerek hücre ölümünü yol açmaktadır. N-Asetilsistein (NAC), anti-oksidan, anti-inflamatuar ve anti-kanserojen etkilere sahip bir ilaçtır. Bu tez çalışmasında, inflamasyonun tetiklenmesi sonrası, LAG3 ve TLR2 reseptörlerinin ekspresyonunda artış görülebileceği ve inflamasyon NAC ile kontrol altına alındığında, inflamasyonun sebep olduğu hasarın azalması ve hücre canlılığında artış görülebileceği hipotezlerinde bulunuldu. Bu varsayımları test etmek amacı ile; in vitro koşullarda deney ve kontrol grupları içeren bir çalışma planlandı. α-syn proteinini aşırı eksprese eden insan nöroglioma (H4) hücre hattı kullanılarak inflamatuar bir Parkinson hastalığı modeli oluşturuldu. İnflamasyon, TNF-α ile tetiklendi ve NAC uygulanarak inflamasyon kontrol altına alındı. Çalışmada α-syn protein ekspresyonu ve transkripsiyonu, Western Blot ve q-PCR metotları ile ölçüldü. Hücre canlılığı Toxilight testi ile, apoptoz Western Blot tekniği ile apoptoz belirteçlerinin ölçülmesi ve TUNEL immunofloresan işaretleme metodu ile değerlendirildi. TLR2 ve LAG3 reseptörlerinin transkripsiyonları q-PCR metodu ile ölçüldü. Reseptörlerin protein düzeyleri immunofloresan işaretleme ve Western Blot tekniği ile saptandı. Elde edilen veriler ışığında, NAC tedavisinin, TLR2 ve LAG3 reseptörlerinin transkripsiyonunu ve ekspresyonunu değiştirerek inflamasyon aracılı toksisiteyi ve hücre ölümünü azalttığı belirlendi. Bu çalışma ile, NAC'nin Parkinson Hastalığında ortaya çıkan nöroinflamasyon süreci için umut vaat eden bir aday olduğu düşünüldü
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Otoimmun ve Vasküler Hastalıklarda Erken Dönemde Endometriyum Reseptivitesinin Değerlendirilmesi
No full textAt each monthly cyle, endometrium undergoes structural changes and renews itself under hormonal control. A healthy endometrium is necessary for a succesful implantation and pregnancy.
Implantation depends on the interaction between the blastocyst and endometrium. During this interaction many molecules such as cytokins [ Leukemia İnhibitory Factor (LIF), Colony-Stimulating Factor-1 (CSF-1), IL-1], growth factors and adhesion molecules (integrins) play important roles. These molecules are controlled by estrogen and progesterone and are synthesized by the endometrium at certain phases of the menstrual cycle and early pregnancy. During the interaction of the blastocyst with the endometrium, different types of ‘cell death’ processes are observed in endometrial epithelial cells and stromal cells. Autophagy is one of them and Beclin-1 is expressed in early autophagy. Recent studies decline the cellular sources and expression mechanisms of these factors. Patients with autoimmune diseases and MTFHR thrombophilia can have recurrent miscarriages.
The aim of this study was to investigate the expression of some of the factors which may play crucial roles in implantation in the normal pregnancies, in patients with autoimmune diseases and MTHFR mutations, and try to compare them to find out the differences which may interfere in implantation in these pregnancies.
Abortus material until 10th gestational-week are used in this study. Group 1; control group (unwanted unwanted induced abortions), Group 2; abortus materials from pregnancies with autoimmun diseases, Group 3; abortus material from pregnancies with hereditary thrombophilia (MTHFR). LIF, IGF-1 and Beclin-1 expressions are investigated immunohistochemically.
In patients with autoimmune diseases and MTHFR thrombophilia, miscarriages are common.
The explanation of the changes of these factors in autoimmune and MTHFR thrombofilia may help to contribute to understand the etiology of unsuccesfull pregnancies in these patients and may help to improve treatment protocols.Endometriyum mensturel siklus boyunca hormonal kontrol altında sürekli yenilenen ve düzenlenen bir dokudur. Gebeliğin sağlıklı bir şekilde oluşabilmesi ve tamamlanabilmesi için; sağlıklı bir endometriyum ve başarılı bir implantasyona ihtiyaç vardır.
Başarılı bir implantasyon için; blastosist ve endometriyum arasında karşılıklı bir etkileşimin olması gerekmektedir. Bu etkileşimde sitokinler [Leukemia İnhibitory Factor(LIF) , Colony-Stimulating Factor-1 (CSF-1), IL-1], büyüme faktörleri ve adezyon molekülleri [İntegrinler] rol oynamaktadır. İmplantasyonda rol alan bu moleküller östrojen ve progesteron tarafından kontrol edilmekte ve endometriyumdan mensturel siklusun belirli evrelerinde ve gebeliğin erken dönemlerinlerinde salgılanmaktadır. Blastosist ve endometrium arasındaki etkileşim sırasında endometriyal epitel ve stomal hücrelerinde farklı hücresel ölüm mekanizmaları gerçekleşmektedir. Bunlardan bir tanesi de otofajidir ve Beclin-1 otofajinin erken dönemlerinde önemli role sahiptir. Yapılan çalışmalarda implantasyonda rol alan bu faktörlerin hangi hücrelerden ve ne zaman salgılandığı gösterilmiştir. Otoimmun ve MTHFR (Metilentetrahidrofolat Redüktaz) trombofilili hastalarda erken dönemde tekrarlayan gebelik kayıpları görülmektedir.
Bu çalışmada normal, otoimmun ve MTHFR trombofilili hastalarda erken gebelik kayıplarında implantasyonda önemli rol alan bu faktörlerin nasıl değiştiği araştırıldı. Çalışmada invitro olarak ilk 10 haftada gebelik kaybı olan hastalardan elde edilen düşük materyalleri kullanıldı. 1. Grup; (kontrol grubu) sağlıklı bireylerin istenmeyen gebeliklerinden, 2. Grup; otoimmun hastalardan ve 3. Grup: MTHFR trombofilili hastalardan elde edildi. Alınan doku örneklerinde LIF, IGF-1 ve Beclin-1 immunohistokimyası yapıldı.
Otoimmun ve MTHFR trombofilili hastalarda halen başarısız gebelikler görülmektedir. İmplantasyonda rol alan faktörlerin bu hastalıklarla ilişkisinin ortaya konması başarılı gebelikler oluşması için yapılan tedavi protokollerine olumlu katkıda bulunacaktır
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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